JP2001214097A - Oxide ink, method for producing the same and method for producing ceramic electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an oxide ink capable of enabling conventional electronic parts to be stably produced by an inkjet method, and further to provide a method for producing the ink, and the method for producing the electronic parts. SOLUTION: The stable printing by the inkjet becomes possible by providing the oxide ink hardly causing sedimentation because the spontaneous sedimentation is prevented, and the oxide ink having higher safety can be provided by optionally using a water-soluble ink.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxidizing method mainly used for manufacturing ceramic electronic components such as multilayer ceramic capacitors, LC filters, composite high frequency components, etc., which are widely used in various electronic devices, using an ink jet. The present invention relates to a product ink, a method for manufacturing the same, and a method for manufacturing a ceramic electronic component.

[0002]

2. Description of the Related Art Conventionally, ceramic electronic components have often been manufactured by a printing method using a plate such as screen printing or gravure printing. However, such a method is suitable for mass production, but it is difficult to make small turns in recent years in the production of small lots and many kinds. Therefore, as a new printing method, it has been proposed to use an ink jet for manufacturing a ceramic electronic component.

For example, Japanese Patent Application Laid-Open No. 8-222475 proposes a method of manufacturing a thick-film type electronic component in which a thick-film ink is applied to an internal electrode pattern by using an ink-jet apparatus, and is laminated and fired. In this case, conductive ink or ink for a resistive film is applied to the surface of the ceramic raw sheet in a predetermined pattern shape by an ink jet device. JP-A-59-82793 proposes forming a conductive adhesive or a low-temperature firing conductor paste at a predetermined connection position on a printed circuit board by an ink jet method. Japanese Patent Application Laid-Open No. 56-94719 proposes that in order to eliminate a step due to the thickness of an internal electrode in a multilayer ceramic capacitor, ceramic ink is sprayed by spraying to produce a reverse pattern of the internal electrode. Similarly, in Japanese Patent Application Laid-Open No. 9-219339, in order to eliminate a step due to the thickness of an internal electrode in a multilayer ceramic capacitor, a ceramic ink is applied to the surface of a ceramic raw sheet by ink jet, and if necessary, an electrode ink is also used. It has been proposed to form by ink jet. In this publication, a multilayer ceramic electronic component is manufactured while continuously guiding a long ceramic raw sheet continuously formed on a carrier film to an internal electrode application station, an oxide ink application station, and a punching station. Will do. In order to absorb such a thickness of the internal electrode, the ceramic raw sheet on which the internal electrode is printed,
In the part where the internal electrode is not formed (remaining part),
Printing oxide ink is disclosed in Japanese Patent Application Laid-Open No. 52-1350.
No. 51 has also been proposed.

Further, in Japanese Patent Application Laid-Open No. 9-232174,
Similarly, it has been proposed that a functional material paste such as a conductive paste or a resistance paste is jetted together with a ceramic paste by an ink jet method to manufacture an electronic component such as a laminated inductor. As a method of manufacturing such a laminated inductor without using a via hole, US Pat.
No. 22,698 proposes a method of manufacturing a laminated coil while alternately forming insulating layers so that a part of a coil pattern is exposed to each other. Also, JP-A-48-8
Japanese Patent No. 1057 proposes a method of laminating coils through via holes formed in a ceramic raw sheet.

In Japanese Patent Application Laid-Open No. 2-65112, it is proposed to improve the characteristics of a semiconductor capacitor by manufacturing a semiconductor capacitor by spraying a required amount of a dopant liquid onto a device surface in the form of a drop in a uniform manner. I have. In this case, in order to dissolve the ionizable salts of the metal, the ink for ink jet is prepared by dissolving it in ethanol or an acid for adjusting pH. As described above, when the electronic component forming member is dissolved in the ink, no precipitate or aggregate is generated in the ink. In addition, as an electronic circuit on the ceramic surface, instead of an electronic circuit, for forming a color or a predetermined image on the ceramic surface, Japanese Patent Application Laid-Open No. 7-330473 discloses an inkjet method using a metal ion aqueous solution. It is proposed to use an organic metal chelate compound in Japanese Patent Publication No. 5-69145 to add water glass and in Japanese Patent Publication No. 6-21255 to add a silicone resin.
However, these proposals are images and cannot form an electronic circuit as proposed by the present invention.

However, in the conventional method of manufacturing various electronic parts by ink jet, a manufacturing method has been proposed, but no practical ink for electronic parts has been proposed. This has a problem that ink containing powder of a metal or the like required for manufacturing such electronic components easily aggregates and easily clogs a jet port of an ink jet apparatus. Next, as an example of a conventional oxide ink, a commercially available oxide ink (dielectric screen ink for a multilayer ceramic capacitor) was diluted with butyl acetate to lower the viscosity, and an example of whether or not it could be used as an ink jet ink was examined. This will be described with reference to FIG.

FIG. 8 is a diagram for explaining a step of ink jet printing using a conventional oxide ink. In FIG. 8, a ceramic raw sheet 2 is formed on a base film 1. This raw ceramic sheet 2 is prepared by dissolving butyral resin in butyl acetate, dispersing barium titanate therein, further adding a phthalic acid-based organic solvent as a plasticizer, and drying on a base film with a coating machine. 30μ
m was used. Reference numeral 3 denotes an ink jet device, from which a built-in oxide ink 5 is ejected as required from a nozzle 4 formed at the tip thereof to form ink droplets 6. The ejected ink droplets 6 adhere to the ceramic green sheet 2 to form an oxide pattern 7. Arrow 8 indicates ceramic raw sheet 2
The figure shows how the solvent component permeates from the oxide pattern 7 into the inside. In this way, when the solvent-based oxide ink 5 adheres to the ceramic green sheet, the solvent component contained in the oxide pattern 7 permeates the ceramic green sheet 2. Reference numeral 9 denotes aggregates generated in the oxide ink 5, and such aggregates 9 precipitate in the oxide ink 5 and clog the nozzles 4.

[0008]

As described above, even if a trial production of an oxide ink for ink jet printing is performed, the nozzles are blocked due to agglomerates in the ink, so that stable printing quality cannot be obtained. was there.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and provides a new and difficult to precipitate oxide ink, a method for producing the same, and a method for producing a ceramic electronic component.

[0010]

According to the present invention, an oxide powder having a particle size of 10 μm or less is dispersed in water or an organic solvent in an amount of 1% to 80% by weight and a precipitate is formed. The viscosity is 10 poise or less at 10 mm or less for 10 minutes or 20 mm or less for 100 minutes. Thereby, precipitation and re-aggregation of the electrode ink for electronic parts are prevented, and stable printing is enabled.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 has a particle size of 1
An oxide powder having a particle diameter of 0 μm or less, and a dispersion of the oxide powder in water or an organic solvent at a concentration of 1% by weight to 80% by weight;
mm or less, the viscosity is 10 poise or less,
Even if the viscosity is as low as 10 poises or less, precipitation hardly occurs, so that it has an effect that printing stability on a printing device such as an ink jet is excellent.

According to a second aspect of the present invention, the content of the first aspect is 100 ppm or less, or the phosphorus content is 1 ppm.
It contains 000 ppm or less of alkali metal, and hardly precipitates even if the viscosity is as low as 10 poise or less, so it has excellent printing stability on a printing device such as an ink jet and the content of alkali metal and phosphorus. Has the effect of providing an oxide ink suitable for producing high-quality ceramic electronic components.

According to a third aspect of the present invention, there is provided a printing apparatus such as an ink jet printer, wherein water or an organic solvent contains a polycarboxylic acid or an organic substance containing a carboxylic acid or a carboxyl group in an amount not more than the weight of the oxide. Has excellent stability in printing, and has the effect of providing an oxide ink with little change over time by adding a carboxylic acid.

According to a fourth aspect of the present invention, there is provided the method according to the first aspect, wherein the water or the organic solvent is a polyvinyl acetal resin;
Polyvinyl alcohol resin, polyvinyl butyral resin, polyvinyl alcohol resin, ethylcellulose resin, methylcellulose resin, or carboxymethylcellulose resin dispersed at least one of them, and printing stability on printing devices such as ink jet Oxide ink with excellent aging and little change over time by adding any one of polyvinyl acetal resin, polyvinyl alcohol resin, polyvinyl butyral resin, polyvinyl alcohol resin, ethyl cellulose resin, methyl cellulose resin, or carboxymethyl cellulose resin Has the effect of being able to provide

According to a fifth aspect of the present invention, a latex resin or an emulsion resin is dispersed in the water or the organic solvent according to the first aspect of the invention. Since it is dispersed together with the resin or the emulsion resin, it has an effect of providing an oxide ink with little change over time.

According to a sixth aspect of the present invention, a nonionic water-soluble resin is dispersed in the water or the organic solvent according to the first aspect, and the printing stability on a printing device such as an ink jet is excellent. The addition of a nonionic water-soluble resin or an ammonium salt thereof has the effect of providing an oxide ink with little change over time.

According to a seventh aspect of the present invention, an ionic additive is dispersed in the water or the organic solvent according to the first aspect, and the printing stability on a printing apparatus such as an ink jet is excellent. Since it is dispersed together with the water-soluble resin, it has the effect of providing an oxide ink with little change over time.

[0018] The invention according to claim 8 is the invention in which
Using beads having a diameter of not less than 10 mmφ, the oxide powder is dispersed in water or an organic solvent in an amount of not less than 1% by weight and not more than 80% by weight and a viscosity of not more than 10 poise together with an additive, and then filtered through a filter. It has excellent printing stability on a printing device such as a jet, and by dispersing and manufacturing using beads such as ceramics, it can provide high-quality oxide ink suitable for ink jet printing with few impurities. Have.

According to a ninth aspect of the present invention, the oxide powder is mixed with water or an organic solvent in a jig made of a hard material at a pressure of 5 kg / cm ² or more and 3000 kg / cm ² or less. A high-quality oxide ink suitable for ink-jet printing, etc., with a small amount of impurities, because the oxide powder is dispersed using a high-pressure disperser. Can be supplied at low cost.

The invention according to claim 10 includes a step of ultrasonically dispersing the oxide powder according to claim 8 in a state of being mixed with water or an organic solvent together with an additive for 1 second to 10 hours. In addition, since the oxide powder is dispersed by using ultrasonic dispersion, it has an effect that an inexpensive high-quality oxide ink suitable for ink-jet printing or the like with a small amount of impurities can be supplied.

In the eleventh aspect of the present invention, the oxide powder of the eighth aspect is mixed with water or an organic solvent together with an additive and dispersed for at least one minute by a high-speed rotating jig at 6 rpm to 10,000 rpm. Including the process,
Since the oxide powder is dispersed by using a high-speed rotating jig, it has an effect that a high-quality oxide ink suitable for ink jet printing or the like with a small amount of impurities can be supplied at low cost.

According to a twelfth aspect of the present invention, the oxide ink according to any one of the first to seventh aspects is applied on a hard plate or a resin film by using an ink jet apparatus to a thickness of 1 μm or more.
It is applied to 0 μm or less, dried to prepare a ceramic raw sheet, an electrode ink is printed on the ceramic raw sheet in a predetermined pattern, laminated, cut, peeled from the hard plate or resin film, fired, Since the external electrodes are formed, the ceramic raw sheet can be easily manufactured by an ink jet apparatus without using an expensive coating machine such as a conventional coater, and the manufacturing costs of various electronic components can be reduced.

(Embodiment 1) The oxide ink according to Embodiment 1 is described as follows: "Oxide having a particle size of 10 μm or less has a viscosity of 10 to 80% by weight and not more than 80% by weight in water or an organic solvent.
Less than poise, precipitation less than 10mm in 10 minutes or 1
Dispersed in 20 minutes or less in 00 minutes. "
Here, as the dielectric powder as the oxide, an oxide such as barium titanate, strontium titanate, alumina, glass, or the like mixed according to the characteristics of an electronic component to be manufactured is used.

As an additive, "a phthalic acid-based solvent such as butyl phthalate or polyethylene oxide" is added. By adding `` cellulose resin, vinyl resin or petroleum resin '' as resin,
It is possible to improve the binding force of the printed coating film and to increase the strength of the dried ink. Examples of the organic solvent include "alcohols such as ethyl alcohol and isopropyl alcohol, ketones such as acetone and methyl ethyl ketone, esters such as butyl acetate, and hydrocarbons such as naphtha".
Is added. If necessary, a dispersant such as "fatty acid ester, polyhydric alcohol fatty acid ester, alkyl glycer ether and its fatty acid, various lecithin derivatives, propylene glycol fatty acid ester, glycerin fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyglycerin fatty acid ester, sorbitan fatty acid By adding "ester, polyoxyethylene alkyl ether, etc.", the dispersibility of the powder becomes good and the precipitation due to the reagglomeration of the powder can be prevented.

Next, dispersion is performed for 3 hours using zirconia beads having a diameter of 0.5 mm. Thereafter, the solution is filtered using a membrane filter having a pore diameter of 5 μm to prepare an organic solvent-based oxide ink having a viscosity of 10 poise.

FIG. 1 shows the state of precipitation of the oxide ink thus prepared. The horizontal axis represents the elapsed time (unit: minute), and the vertical axis represents the thickness of the supernatant layer (unit: mm). is there. FIG. 2 shows an example of measurement of precipitation of the oxide ink.

In FIG. 2, 10 is a glass tube, 11 is an electrode solution, and 12 is a supernatant layer. In order to measure the precipitation of the ink, first, as shown in FIG. 2A, a predetermined amount of the electrode solution 11 in a dispersed state is put into a glass tube 10 (preferably at least 10 mm in diameter and at least 10 cm in depth). Then, the state of the electrode solution is observed along with the elapsed time (the unit is minutes).
Then, the upper surface of the electrode solution 11 (so-called meniscus surface)
Then, the supernatant layer 12 is gradually formed, and the thickness of the supernatant layer 12 increases as the elapsed time increases. FIG. 1 shows a graph of the thickness of the supernatant layer 12 measured in this manner with respect to the elapsed time. Generally, since the electrode solution 11 contains a predetermined amount of metal powder, it is black and does not transmit light.
On the other hand, the supernatant layer 12 contains little metal powder and is transparent and transmits light. Thus, the electrode solution 11 and the supernatant layer 12 are optically distinguishable. The supernatant layer 12 and the electrode solution 11 can be easily distinguished even when the specific gravity and the solid content of each solution are different.

In FIG. 1, A, B, and C show the results of measurement of the precipitation of each oxide ink. Among A to C, A is the least likely to precipitate, and C is the most easily precipitated. . In B, the thickness of the supernatant layer after 10 minutes is 10 mm, and the thickness of the supernatant layer after 100 minutes is 20 mm. As the oxide ink used in the ink jet, an ink having the same or lower sedimentation rate than B is desirable. In the case of the oxide ink which easily precipitates as shown in A, precipitation occurs inside the ink jet device, so that stable printing cannot be performed.

In order to reduce the sedimentation rate,
It is effective to adsorb various resins on the surface of the metal powder contained in the oxide ink. To preferentially adsorb the resin to the oxide, a carboxylic acid or fatty acid having a carboxyl group in the side chain of the resin, or a polycarboxylic acid resin having a plurality of carboxyl groups is preferable. In addition, a resin containing a hydroxyl group in addition to a carboxyl group is also easily adsorbed on the powder surface, and has an effect of preventing precipitation.

In order to prevent precipitation of the ink powder,
Although it depends on the specific gravity of the powder, the particle size is desirably 10 μm or less. When the particle size is larger than 10 μm, it is difficult to make the precipitation rate slower than B in FIG. 1 even if the absolute value of the surface potential of the metal powder is increased or various fatty acid-based resins are adsorbed on the surface. The sedimentation speed of the metal powder can be reduced as shown in FIG.

The content of the metal powder in the ink is preferably from 1% by weight to 80% by weight. When the content is 0.5% by weight or less, the oxide powder hardly precipitates (according to the experiments by the inventors, it is considered that the average distance between the powders is large and it is difficult for the powder to collide). In many cases, the required sintered density cannot be obtained. In the case of a high-concentration ink of 90% by weight or more, the average distance between the oxide powders is too short. Therefore, no matter how much the zeta potential is increased, agglomeration occurs in a short time. In some cases, stable printing is difficult even with the use of an apparatus, which is unsuitable for manufacturing electronic components.

Although the oxide ink of the first embodiment is of an organic solvent type, it may be a water-based oxide ink.
In this aqueous oxidized particle ink, 1 g of an additive or a resin and 150 g of water or an aqueous (or water-soluble) organic solvent are added to 100 g of an oxide powder mainly composed of barium titanate having a particle size of 0.4 μm. Next, dispersion is performed for 3 hours using zirconia beads having a diameter of 0.5 mm. Thereafter, the mixture is filtered using a filter to prepare a water-based oxide ink having a viscosity of 10 poise.

The water-based oxide ink will be described in more detail. Here, as the aqueous (or water-soluble) organic solvent, ethylene glycol, glycerin, ethylene glycol or the like is added. As the resin, by adding a water-soluble resin such as a cellulose resin such as methylcellulose and carboxymethylcellulose, a vinyl resin such as polyvinyl alcohol, and a latex resin such as styrene-butadiene rubber, the binding force of the printed coating film is improved. After drying, the strength of the ink can be increased. Examples of dispersants include various lecithin derivatives, propylene glycol fatty acid esters, glycerin fatty acid esters, polyexethylene glycerin fatty acid esters, polyglycerin fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbit fatty acid esters, and polyethylene glycol. By adding a fatty acid ester, polyoxyethylene alkyl ether, polycarboxylic acid or various soaps, the dispersibility of the powder can be improved, and precipitation due to reagglomeration of the powder is prevented.

As described above, especially in the case of a water-soluble oxide ink, it is desirable to increase the absolute value of the zeta potential of the oxide powder in the ink in order to reduce the precipitation rate of the ink.
First, the inventors conducted experiments on barium titanate, alumina, glass powder and the like as oxides. Inventors have been using ES
As a result of analyzing the surface of these oxides using a surface analyzer such as CA, it was found that the powder surface had a thickness of several nm and was covered with a hydrated layer or a hydroxide layer. Therefore, it has been found that when added to water, the powder takes on a positive or negative zeta potential (depending on the pH of the liquid). Therefore, an additive was added to the ink to increase the surface potential. According to the experiments by the inventors, it was found that, in order to make the precipitation slower than in FIG. 1B, it is desirable that the absolute value of the zeta potential of the oxide powder be 40 mV or more. Also, depending on the powder and additives, the zeta potential is between -60 mV and -70 m between pH 2 and pH 12.
In some cases, the absolute value of V (about -100 mV) and the absolute value of the zeta potential can be extremely high (equipotential points were obtained, but it was impossible to measure the equipotential points at pH in the measurement region). Thus, an oxide ink having a stable dispersion was obtained. As described above, by setting the zeta potential of the oxide to 40 mV or more in absolute value, an oxide ink that hardly precipitates as shown in FIG. 1B can be provided. For comparison, various commercially available oxide inks (mainly for screen printing) such as glass and dielectric were obtained and diluted with a special solvent. As a result, as shown in FIG. The printing experiment was attempted by setting the printer in a commercially available ink jet apparatus, but no stable printing was obtained.

As described above, by using the water-soluble solvent,
There is no dissolution or swelling of the plastic member constituting the ink jet device. In addition, it has less odor than organic solvent-based inks, and can promote further safety measures and environmental measures such as fire prevention and compliance with the Fire Service Law.

(Embodiment 2) The oxide ink according to Embodiment 2 is described as having an alkali metal content of 1000 pp.
m or less, or a phosphorus content of 10,000 ppm or less "and an oxide ink having a viscosity of 10 poise or less. By thus reducing the content of the alkali metal, the reliability of the electronic component (particularly, the reliability when a voltage is applied) can be increased.
For example, when metal soap or a compound thereof is used as an additive for an oxide ink, if the content of an alkali metal in the dielectric ink exceeds 10,000 ppm, the reliability may be reduced depending on the product. Similarly, when a dispersant containing phosphorus is added as an additive of the oxide ink,
If it exceeds 00000 ppm, the reliability may be lowered or the electrical characteristics (for example, the dielectric constant and the temperature characteristics) may be affected depending on the product. For this reason, the content of the alkali metal contained in the oxide ink (especially the dried coating film) is 10%.
It is desirable that the content of phosphorus is not more than 00 ppm and the content of phosphorus is not more than 10,000 ppm. For analysis of such elements, a high-precision analysis method such as atomic absorption can be used.

Examples of the phosphate include "sodium hexametaphosphate, polyoxyethylene-added linear alcohol phosphate, polyoxyethylene-added alkylphenol phosphate, alkyl phosphate, etc." Examples of the anionic surfactant include carboxylic acid salts such as “linear aliphatic salt, coconut oil fatty acid salt, tall oil fatty acid salt, amine salt, N salt,
-Lauroylsaccosin, acylated polypeptides and the like ". As the sulfonate, "linear alkylbenzene sulfonate, triethanolamine salt, isopropylamine salt, free sulfonate, higher alkylbenzene sulfonate, benzene, toluene, xylene, cumene sulfonate, lignin sulfonate, petroleum sulfone Acid salt, N
-Acylalkyl taurate, n-paraffin sulfonate, α-olefin sulfonate, sulfosuccinate, alkylphthalene sulfonate, isethionate and the like. Examples of the sulfate include “linear primary alcohol sulfate (AS), polyoxyethylene-added linear alcohol sulfate (AES), sulfate (sulfonated oil) and the like”.

Examples of the cationic surfactant include linear amines, linear diamines, linear polyamines, linear quaternary ammonium salts (eg, tetraalkylammonium salts and N-alkyltrimethylammonium chloride), and polyoxyethylene. Addition linear amine, polyoxyethylene addition linear quaternary ammonium salt, amine oxide (for example, N-
Cetyldimethylamine oxide or the like can be used as the alkyldimethylamine oxide. Examples of the nonionic surfactant include a polyoxyethylene-added nonionic surfactant, an ethylene oxide adduct of an alkylphenol (APE), an ethylene oxide adduct of a linear alcohol (AE), a polyoxyethylene adduct of a polyoxypropylene glycol, Polyoxyethylene adducts of linear mercaptans, linear aliphatic esters, glyceryl, polyglyceryl esters of natural fatty acids, propylene glycol, sorbitol, fatty acid esters of polyoxyethylene-added sorbitol, polyoxyethylene glycol esters, polyoxyethylene-added fatty acids ( Tall oil), alkanolamine-fatty acid condensate, alkanolamide, acetylene tertiary glycol, polyoxyethylene-added silicone, N-alkylpyrrolidone, alkyl There is a polyglycosides "and the like.

Examples of the amphoteric surfactants include “β-N-alkylaminopropionic acid, N-alkyl-β-iminodipropionic acid,
There are "isodazoline carboxylic acid, N-alkyl betaine, and amine oxide", and as the pH-insensitive surfactant, "sulfovitain, salt" and the like can be used.

In order to make the precipitation rate of the electrode ink for electronic parts proposed in the present invention slower than that of FIG. , The surface potential of the metal powder can be relatively increased, and an electrode ink for electronic parts as shown in FIG. 1 (A) can be obtained. And stable ink jet printing was obtained.

FIG. 3 is a diagram for explaining a method of manufacturing a multilayer ceramic electronic component according to the first embodiment of the present invention. In FIG. 3, reference numeral 13 denotes a base film, on which a ceramic raw sheet 14 is formed. Reference numeral 15 denotes an electrode ink for electronic parts, which is formed on the ceramic green sheet 14 in advance by screen printing, gravure printing, ink jet printing, or the like. Reference numeral 16 denotes an oxide ink, which is filled in an ink jet head 17. Reference numeral 18 denotes an element, which is formed inside the ink jet head 17 and generates local heat and a piezoelectric effect. By the function of the element 18, the ink droplet 19 is ejected from the ink jet head 17 as needed. The ink droplets 19 form an ink pattern 20 on the upper surface of the ceramic raw sheet 14.

First, a dielectric powder mainly composed of barium titanate having a particle size of 0.5 μm and having a X7R characteristic according to EIAJ standard is dispersed together with a butyral resin, a phthalic acid plasticizer and an organic solvent to form a dielectric slurry. After this slurry is filtered with a 10 μm filter, it is applied on a resin film 13 to form an organic ceramic green sheet 14 having a thickness of 10 μm.

Next, as shown in FIG. 3, an electrode ink 15 for electronic parts is printed in a predetermined shape on the upper surface of the ceramic raw sheet 14 by using a printing method such as gravure, ink jet, or screen. After that, the ink jet head 17 forms the oxide ink 16 in a predetermined shape (for example, in a pattern that absorbs the thickness of the internal electrode). First, the oxide ink 16 described in the first embodiment is ejected on demand as small droplets by the built-in element 18 as needed. The ejected ink droplets 19 adhere to the surface of the raw ceramic sheet 14 to form an ink pattern 20. Element 18
By regularly arranging several to several hundred (not shown), a large number of ink droplets 19 can be ejected at the same time, and the printing speed can be increased.

Next, while peeling off the base film 13 from the ceramic raw sheet 14 having the ink pattern 7 in the previous step, several hundred sheets are pressed on the uppermost surface and the lowermost surface, if necessary, from the upper limit. The device is pressed and pressed to form a ceramic green laminate.

Finally, the ceramic green laminate is cut into desired dimensions and singulated, and external electrodes electrically connected to the ink patterns 20 as internal electrodes are formed to produce a multilayer ceramic electronic component. Things. As described above, in the case where the thickness of the electronic component electrode ink 15 is absorbed by using the oxide ink 16, even when 600 layers are laminated, no distortion or the like due to the thickness or presence or absence of the internal electrode occurs. Was. For comparison, in the case where the printing of the oxide ink by the ink jet was not performed, distortion due to the thickness and presence or absence of the internal electrode occurred in the lamination of 100 layers or more.
Lamination of more than 00 layers was not possible. In particular, by using the ink jet method to absorb the thickness of the internal electrode, the actual internal electrode printing pattern (for example, bleeding and sagging of the electrode ink, (In consideration of elongation, etc.), and more flexible production can be performed.

FIG. 4 is a diagram comparing the printing stability of the oxide ink of Embodiment 1 and the oxide ink of the present invention in an ink jet apparatus. In FIG. 4, the horizontal axis represents the number of continuous printed sheets (unit). Is the number of sheets), and the vertical axis is the amount of ink applied (unit is mg / cm ² ). FIG. 4 shows the printing stability with an ink jet by comparing the relationship between the number of continuous prints and the amount of ink applied. In FIG. 4, the open circles are conventional oxide inks, and the amount of ink applied sharply decreased with an increase in the number of printed sheets. On the sixth sheet, the ink ejection portion was blocked and printing could not be performed. On the other hand, in the case of the oxide ink according to the first embodiment shown by a black circle, printing can be stably performed even when the number of sheets exceeds 200.

(Embodiment 3) The oxide ink according to Embodiment 3 is an oxide ink to which an organic substance containing "polycarboxylic acid, carboxylic acid, carboxyl group" is added. According to the experiments of the inventors, such organic substances containing a carboxyl group are particularly effective in dispersing oxides in water or a water-soluble organic solvent, and furthermore, the organic substance itself contains alkali metal, phosphorus, and the like. Since it does not contain, it hardly affects the characteristics of the electronic component.

As the organic substance containing a carboxylic acid, various substances having a molecular weight of tens to tens of thousands are known, and can be optimized depending on the kind and particle size of the oxide. By using such an ammonium salt of a carboxylic acid, the content of alkali metal in the oxide ink can be further suppressed, and a highly reliable ceramic electronic component can be manufactured.

In particular, in the case of an oxide ink having a viscosity of 10 poise or less, the lower the viscosity, the faster the powder precipitates, so that printing becomes difficult. However, as shown in the present invention,
By adding various additives, even with a low-viscosity oxide ink of, for example, about several centipoise, the precipitation rate can be reduced as shown in FIG. 2, so that application and printing with an ink jet become easy.

(Embodiment 4) The oxide ink according to Embodiment 4 is made of "polyvinyl acetal resin, polyvinyl alcohol resin, polyvinyl butyral resin,
Polyvinyl alcohol resin, ethyl cellulose resin,
An oxide ink dispersed with at least one of a methylcellulose resin and a carboxymethylcellulose resin. " As described above, the oxide powder is dispersed together with the resin, and the viscosity can be reduced to 10 poise or less and the precipitation can be reduced to 10 mm or less in 10 minutes or 20 mm or less in 100 minutes. According to experiments by the inventors, such a resin can be adsorbed on the surface of the oxide and can slow down the precipitation of the oxide. In addition, when the viscosity is 20 poise or more, depending on the ink jet device, the jetting property of the ink may decrease,
Viscosity of ink is 10
Poise or less is desirable.

(Embodiment 5) The oxide ink in Embodiment 5 is an oxide ink "dispersed with a latex resin or emulsion resin". As described above, the amount of resin contained in the oxide ink is increased by using the resin in an emulsion or latex state (that is, a resin solution in which the resin is dispersed in water or a solvent as fine particles of 0.1 mm or less). Even so, the ink viscosity can be kept at 10 poise or less. For example, when a general resin is dissolved in a solvent at a high concentration of several tens wt%, the viscosity may be as high as 100 poise or more,
In the case of such an emulsion type resin, the resin concentration is 50%.
%, The viscosity can be kept at 1 poise or less. For this reason, even if the amount of resin is increased, an increase in the viscosity of the ink can be minimized, so that an oxide ink that can be stably used by the ink jet method can be provided.

(Embodiment 6) The oxide ink according to Embodiment 6 is “dispersed in water or an organic solvent in an amount of 1% to 80% by weight together with a nonionic water-soluble resin”. It is. As described above, by using a nonionic water-soluble resin, even when an additive having various functional groups (for example, a carboxyl group, a hydroxyl group, a carbonyl group, etc.) is added to the ink in addition to the resin, such an ink is used. The possibility of forming an aggregate, a precipitate, a gel-like substance, or the like by reacting with the additive can be reduced. In this manner, by preventing the organic substances added to the ink from reacting with each other, the filterability of the ink is enhanced, and stable ink jet printing without ink clogging is enabled.

(Embodiment 7) The oxide ink according to Embodiment 7 is obtained by adding an “ionic additive”, and by adding an ionic additive and adsorbing it on the oxide surface, the oxide ink is oxidized. The absolute value of the potential on the object surface can be increased, and the precipitation of oxide can be suppressed. In this way, even if the oxide ink has a low viscosity of 10 poise or less and easily precipitates, the precipitation is 10
It is suppressed to 10 mm or less per minute, or 20 mm or less in 100 minutes, and stable ink jet printing for a long time becomes possible.

(Embodiment 8) The oxide ink according to Embodiment 8 is obtained by dispersing oxide powder together with additives in water or an organic solvent using "beads having a diameter of 0.01 mm to 10 mm". In addition, since the additive can be adsorbed on the surface of the dissolved oxide at the same time as the oxide is disintegrated, the oxide ink can be manufactured in a short time. The oxide ink thus produced hardly precipitates and therefore has a viscosity of 10%.
When diluted to less than poise, the precipitate is reduced to 1 in 10 minutes.
It is suppressed to 0 mm or less, or 20 mm or less in 100 minutes, and long-term stable ink jet printing becomes possible. The diameter of the beads is desirably 0.01 mmφ or more and 10 mmφ or less. Beads with a diameter of 0.005 mmφ or less are difficult to separate after ink preparation, and beads with a diameter of 15 mmφ or more have low dispersion efficiency and are not practical.

When the electrode ink for electronic parts is manufactured by using a bead mill, a diameter of 0.01 μmφ to 10 mm
It is desirable to use beads of φ or less. 0.005μ
With beads of m or less, it is difficult to remove the beads after dispersion. In the case of beads having a diameter of 15 mmφ or more, the dispersion efficiency is deteriorated and the metal powder may be deformed. When such beads are used, a commercially available electric type vertical or horizontal bead mill, or a ball mill used by being set on a rotating frame or the like can be used. The rotation speed of such a mill is desirably from 10 rpm to 2,000 rpm. When the bead mill is at 5 rpm or less, the dispersion efficiency is reduced, which is not practical. On the other hand, in a high-speed bead mill exceeding 3000 rpm, the collision between beads becomes severe, the dispersion efficiency decreases, the bead life is shortened, and impurities easily enter the ink.

(Embodiment 9) The oxide ink according to Embodiment 9 is described as having a pressure of 5 kg / cm ² or more and 3000 kg.
At a pressure of not more than / cm ² , through a jig made of a hard material. By dispersing under such high pressure, ink can be prepared in a short time. At a pressure of 5 kg / cm ² , the pressure is too low to produce an oxide ink. At a pressure of 3500 kg / cm ² or more, the hard material may be shaved by the ceramic member and mixed into the oxide ink as impurities. At such a high pressure, the equipment becomes special, and equipment costs, workability, and safety measures become more necessary.
Not common.

A method for producing an electrode ink for electronic parts will be described with reference to FIG. FIG. 5 is a diagram illustrating an example of a high-pressure dispersion device. In FIG. 5, 21 is a hopper, 22
Is a pressure generating unit, 23 is a dispersing unit, 24 is a cooling unit, and 25 is an ink outlet. First, the ink (not shown in FIG. 5) supplied from the hopper 21 is sent to the dispersion unit 23. A hydraulic pump or the like is built in the pressure generating unit 22, and the pressure generated in the pressure generating unit 22 is
Sent to The ink sent to the inside of the dispersion unit 23 (FIG. 5)
Are dispersed under high pressure inside the dispersion unit 23 and cooled inside the cooling unit 24,
It is discharged from 5. The electrode ink for electronic parts can be more highly dispersed by passing through the high-pressure dispersing device a plurality of times as necessary. As such a high-pressure dispersing apparatus, commercially available products such as a homogenizer manufactured by Gorin, USA, a microfluidizer manufactured by Microfluidizer, Inc., an Ultimateizer manufactured by Sugino Machine Co., Ltd., and a Nanomizer manufactured by Japan Nanomizer Co., Ltd. can be used.

FIG. 6 is a view for explaining the inside of the dispersion section of the high-pressure dispersion apparatus. Reference numeral 26 denotes a hard material, which can be made of ultra-high metal, ceramic, diamond or the like to prevent abrasion. FIG. 6A shows a case where the ink is hit against a hard wall and dispersed, and FIG. 6B shows a case where the ink ejected from a plurality of openings is hit and dispersed. FIG.
3A, the electrode ink flows at high speed in the direction of the arrow in the ink passage formed in the hard material 26, and is struck and dispersed at high speed on the hard material 26. FIG.
In (b), the electrode ink flows at high speed in the direction of the arrow in the inside of the plurality of ink passages formed in the hard material 26, and the inks are struck at high speed, merged and dispersed. The inside of the dispersing section may have a shape other than that shown in FIG. 6. However, when manufacturing an electrode ink for electronic parts used in an ink jet, the pressure is 5 kg / cm ² or more.
It is desirable that it be 000 kg / cm ² or less. When the pressure is less than 5 kg / cm ² , the dispersion of the ink is insufficient, and the ink precipitates inside the ink jet device,
May re-aggregate. The pressure is 4000 kg / cm ²
In the case described above, the device becomes highly rigid, the manufacturing cost increases, and further safety measures are required.

(Embodiment 10) The oxide ink according to Embodiment 10 is prepared by using "ultrasonic waves". Here, a single or a plurality of frequencies of 10 KHz or more and 10 MHz or less can be used as the ultrasonic waves. When one liter of ink is placed in a plastic container and dispersed by ultrasonic waves, it is desirable to use ultrasonic equipment having an output of 50 W or more. If the power is less than 50 W, the output is insufficient, which is not practical. Therefore, 2
By using a large-sized ultrasonic facility of 00 W or more, dispersion can be performed in a short time, and the production cost of the oxide ink can be reduced. In addition, there are an ultrasonic device in which a sample is immersed in a water tank and a device in which a projection type transmitter is used in the sample, and either of them may be used.

Hereinafter, a method for producing an electrode ink for electronic parts will be described. First, as the electrode ink, 100 g of copper powder having a particle size of 1 μm and 100 g of an organic solvent were added as metal powder. In addition, 1 g of a dispersant and 2 g of a high boiling organic solvent as a plasticizer were added. Next, the mixture was dispersed in a commercially available automatic mortar for 30 minutes. Next, put this electrode ink in a commercially available plastic bottle,
It was set in an ultrasonic dispersing machine and ultrasonically dispersed.

The ultrasonic dispersion may be used not only in the production of the electrode ink for electronic parts but also in the step of printing with an ink jet apparatus. For example, a commercially available ultrasonic water tank can be used as the thermostat 21 in FIG.
By doing so, the ink tank 21 can always be ultrasonically dispersed as needed (it may be stirred using a stirrer or the like at the same time), and furthermore, sedimentation and reaggregation of the ink can be prevented. Also, by ultrasonic dispersion, dissolved oxygen and the like dissolved inside the electrode ink for electronic parts can be removed,
It is possible to prevent the generation of bubbles in electrode ink for electronic parts,
There is no need to worry about filling the ink jet device with air bubbles.

When manufacturing an electrode ink for electronic parts, the ink can be dispersed in a shorter time by using an ultrasonic generator that inserts an ultrasonic oscillator directly into the ink. Also, when printing the completed electrode ink for electronic parts using an ink jet device, the above-described ultrasonic generator with a water tank can be used to disperse ultrasonic waves from outside the ink tank. There is no contamination such as garbage. The ultrasonic dispersion time is desirably from 1 second to 10 hours. At less than 0.5 seconds, there is no effect of ultrasonic dispersion. Ultrasonic dispersion for more than 10 hours is not efficient and may shorten the life of the ultrasonic dispersion equipment.

(Embodiment 11) The oxide ink according to Embodiment 11 is prepared by using a "high-speed rotating jig". Here, as the high-speed rotating jig, it is desirable that a high-speed rotating jig is directly attached to the tip of a motor capable of high-speed rotation, and the high-speed rotating jig is immersed in oxide ink and rotates at a high speed. The rotation speed is 6
It is desirable that the rotation speed is not less than rpm and not more than 50,000 rpm. 6 rpm
If it is less than the above, sufficient shear cannot be applied to the oxide ink. When the rotation speed exceeds 60000 rpm, even if a very small high-speed rotating jig is used, it is not practical because the jig itself may be damaged by centrifugal force.

FIG. 7 illustrates an example of a rotary dispersion machine. In FIG. 7, the oxide ink 16 is stored in a tank 27.
Is set in Reference numeral 28 denotes a rotating device, to which a jig 29 is attached at the tip. The jig 29 is rotated at high speed in the direction of the arrow by the motor built in the rotating device 28 to disperse the oxide ink 16 in the tank 27. Reference numeral 30 denotes the curvature of the bottom edge of the tank 27, which has a certain curvature or more as shown in FIG. Specifically, 5m in diameter
It is desirable that the bottom edge of the tank 27 has a curvature 30 of m or more. When the curvature 30 of the bottom edge of the tank 27 is 1 mm or less, the convection of the ink in this portion may be hindered and the dispersion may be insufficient, which is not desirable for the dispersion of the oxide ink. The rotation speed of the rotation device 28 is 60 rpm or more and 50,000 r at the time of manufacturing the electrode ink for electronic parts.
pm or less is desirable. At a low speed of 50 rpm or less, the dispersion of the ink may be insufficient. Also 100000r
When high-speed dispersion at pm or more is performed, the equipment is special, large-scale, and difficult to handle.

Incidentally, an automatic mortar or a high-viscosity dispersing machine such as a commercially available kneader, premixer or planetary mixer may be used in advance. By dispersing the ink in advance using such a dispersing machine and then dispersing the ink using a high-speed rotating jig as described in Embodiment 11, it is possible to produce an oxide ink that is less likely to precipitate and reduce the production cost.

(Twelfth Embodiment) In the twelfth embodiment,
A method for producing a ceramic green sheet using an oxide ink will be described. In this embodiment, the oxide ink 1 is directly placed on the base film 13 in FIG.
6 is applied and formed using an ink jet head 17. Next, by drying the oxide ink 16, the green ceramic sheet 14 can be formed on the base film 13. If necessary, the electronic component electrode ink 15 and the oxide ink 16 can be formed on the ceramic raw sheet 14 by an ink jet or the like as described in the first embodiment and the like.

For comparison, as a conventional method for manufacturing a raw ceramic sheet, there is a method using a reverse coater or a doctor blade coater. However, in such a conventional method, the cost is higher than the cost of equipment, so that several hundred kg is required. It is suitable for producing a large quantity of ceramic green sheets at a time using the above oxide ink. On the other hand, in the present embodiment, for example, even tens of g of the oxide ink can be manufactured as a ceramic raw sheet without waste. Further, since the application width, application length, thickness, etc. of the ceramic raw sheet itself can be freely adjusted, it is suitable for the production of electronic components of various kinds in small quantities. In addition, since the ink jet method is used, the ceramic raw sheet is formed in a pattern (for example, several cm square,
Or via holes formed, or intermittent coating)
Thus, it can be formed as a free shape. For this reason, there is no need for a slicer that cuts the width of the ceramic green sheet, a puncher that forms a hole in the ceramic green sheet in a predetermined shape, a mold that punches the ceramic green sheet into a predetermined shape, and an accompanying press device that were required in the past. Therefore, further cost reduction is possible.

When a ceramic green sheet is formed on a hard plate or a resin film by using an ink jet, it is desirable that the thickness be 1 μm or more and 100 μm or less. Even if an attempt is made to form a ceramic raw sheet having a size of 0.5 μm or less by ink jet, it is not practical because the thickness variation tends to occur due to the ink droplets 19. Further, when forming a thick ceramic green sheet exceeding 150 μm, it takes too much time and is not practical.

By repeating the twelfth embodiment and the first embodiment a plurality of times, a predetermined ceramic electronic component can be manufactured. In addition, by forming a plurality of layers each from the oxide ink and the electrode ink on a hard plate or a resin film (while connecting with via holes or the like as necessary), a more complex ceramic electronic component can be formed. . In addition, here, as for the ink jet device, even if it is of an on-demand type (a device that applies oxide ink only when necessary), it is a continuous type (an ink collecting mechanism called a gutter when ion droplets are constantly ejected). Only when the ink is collected and printed, the flight direction of the ink is changed to the direction of the printing material by the force of static electricity or the like).

[0070]

As described above, according to the present invention, it is possible to provide a high-concentration oxide ink in which the generation of precipitates and aggregates is suppressed. Therefore, not only multilayer ceramic electronic components such as multilayer ceramic capacitors, but also high-frequency components,
When necessary, electronic parts such as optical parts, LC filters, three-dimensional composite electronic parts, and composite devices with various semiconductors can be manufactured by ink jet or gravure printing in the shortest time necessary. Higher yield and higher reliability can be achieved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a state of precipitation of an oxide ink according to Embodiment 1 of the present invention.

FIG. 2 is a view for explaining an example of measurement of precipitation of the oxide ink.

FIG. 3 is a diagram illustrating a method of manufacturing the multilayer ceramic electronic component.

FIG. 4 is a diagram comparing printing stability between the ink jet device and a conventional ink jet device.

FIG. 5 is a diagram illustrating an example of the high-pressure dispersion device.

FIG. 6 is a view for explaining an example of the inside of a dispersion unit of the high-pressure dispersion device.

FIG. 7 is a diagram illustrating an example of a rotary dispersion machine.

FIG. 8 is a diagram illustrating a process of performing ink jet printing with a conventional oxide ink.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 base film 2 ceramic raw sheet 3 ink jet device 4 nozzle 5 oxide ink 6 ink droplet 7 oxide pattern 8 arrow 9 aggregate 10 glass tube 11 electrode solution 12 supernatant layer 13 base film 14 ceramic raw sheet 15 for electronic components Electrode ink 16 Oxide ink 17 Ink jet head 18 Element 19 Ink droplet 20 Ink pattern 21 Hopper 22 Pressure generation part 23 Dispersion part 24 Cooling part 25 Ink outlet 26 Hard material 27 Tank 28 Rotating device 29 Jig 30 Curvature

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4J039 AB02 AD06 AD07 AD18 AE07 BA13 BA15 BA19 BA25 BA29 BA30 BA32 BA35 BA39 BC19 BC20 CA06 CA07 EA41 EA44 EA48 FA02 FA07 GA24 5E001 AB03 AE01 AE02 AE03 AH01 AJ02 5E08 EE01 AE03 EE35 FF05 FG06 FG26 FG46 FG54 LL02 PP03 PP05 PP07 PP08 PP09 PP10

Claims (12)

[Claims] 1. An oxide powder having a particle size of 10 μm or less, and a dispersion of the oxide powder in water or an organic solvent in an amount of 1% by weight to 80% by weight and precipitation of 10 mm or less in 10 minutes or 20 mm in 100 minutes. An oxide ink having a viscosity of 10 poise or less in the following. 2. The oxide ink according to claim 1, comprising an alkali metal having a content of 100 ppm or less or a phosphorus content of 1000 ppm or less. 3. The oxide ink according to claim 1, wherein water or an organic solvent contains a polycarboxylic acid or an organic substance containing a carboxylic acid or a carboxyl group in an amount not more than the weight of the oxide. 4. A dispersion of at least one of polyvinyl acetal resin, polyvinyl alcohol resin, polyvinyl butyral resin, polyvinyl alcohol resin, ethyl cellulose resin, methyl cellulose resin, and carboxymethyl cellulose resin in water or an organic solvent. The oxide ink according to claim 1. 5. The oxide ink according to claim 1, wherein a latex resin or an emulsion resin is dispersed in water or an organic solvent. 6. The oxide ink according to claim 1, wherein a nonionic water-soluble resin is dispersed in water or an organic solvent. 7. The oxide ink according to claim 1, wherein the ionic additive is dispersed in water or an organic solvent. 8. An oxide powder having a viscosity of 10 to 80% by weight in water or an organic solvent together with an additive using beads having a diameter of 0.01 to 10 mm in water or an organic solvent.
A method for producing an oxide ink that is dispersed below a poise and then filtered through a filter. 9. A pressure of 5 kg / cm ² or more and 3000 kg / cm ² or more.
9. The method for producing an oxide ink according to claim 8, further comprising a step of passing the oxide powder with water or an organic solvent at least once in a jig made of a hard material at a pressure of not more than cm ^2. Method. 10. The method for producing an oxide ink according to claim 8, further comprising a step of ultrasonically dispersing the oxide powder in a state of being mixed with water or an organic solvent together with the additive for 1 second to 10 hours. 11. In a state in which the oxide powder is mixed with water or an organic solvent together with an additive, the mixture is not less than 60 rpm and not more than 50,000.
9. The method for producing an oxide ink according to claim 8, further comprising a step of dispersing for 1 minute or more by a high-speed rotating jig at not more than rpm. 12. The oxide ink according to claim 1, which is applied to a hard plate or a resin film with a thickness of 1 μm or more and 100 μm or less using an ink jet device.
Drying to produce a ceramic raw sheet, printing and laminating an electrode ink on the ceramic raw sheet in a predetermined pattern, cutting and then peeling from the hard plate or resin film, firing, and forming a ceramic to form an external electrode Manufacturing method of electronic components.